Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HAC > Tail Rotor > Flashcards

Tail Rotor Flashcards

1
Q

Provides directional control by

A

varying pitch of TR blades

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

TR is __ actuated, but requires __ to operate the pitch change shaft, which moves the ___, changing blade pitch angle through ___

A

mechanically; hydraulic pressure; pitch change beam; pitch change links

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

TR quadrant transmits TR cable movement to the

A

TR servo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

__ connected to the quadrant allow cable tension to be maintained if either TR cable becomes severed

A

2 spring cylinders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

if both cables are severed, __ will counter TR servo pilot valve to position TR to neutral for fly home capability

A

2 separate centering springs

positions pedals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the TR

A

bearingless, crossbeam TR blade system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

TR flexible spar allows

A

tail rotor blade flap and pitch change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Blades are canted

A

20 degrees upward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

TR provides __ % of lift in a hover which helps __

A

2.5; lower nose attitude in hover because the TR is aft of the aircraft CG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

TR indexing system

A

positions blades during pylon folding and prevents TR from windmilling in winds up to 60 knots when tail folded

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe TR blades

A

built around 2 composite spars to form 4 blades

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Nose snap with loss of drive is less noticeable at __ airspeeds

A

faster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Indication of functioning TR when attempting to verify drive failur

A

application of right pedal brings nose right

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

3 types of TR Control Malfunctions

A
  1. Cable failure
  2. Servo failure
  3. Restricted flight controls
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Cable failure indications

A

TR QUADRANT light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cable failure airspeeds for GW 19,500 lbs

A

25 AND 145 KIAS

17
Q

Cable failure below/above 25/145; between 25/145

A

Nose yaws right; nose yaws left

18
Q

TR Servo Failure indications

A

Lose No 1 Hyd Pump and Backup Pump; retain boost and mechanical system

19
Q

TR Servo Airspeeds

A

40 TO 120

20
Q

Servo Failure Recommended Landing

A

Running landing above 40 KIAS

21
Q

Restricted Flight Control Scenarios

A

FOD, mechanical failure, servo hardover

22
Q

Hardover failure can put __ lbs of force on pedals

A

250 lbs

23
Q

Stuck left

A

high power setting; normal landing

24
Q

Stuck right

A

low power setting, running landing/auto

25
Q

LTE

A

inability of TR to provide sufficient force to maintain yaw controllability

26
Q

LTE occurs when

A

full pedal input is insufficient to provide directional control

27
Q

Tail rotor thrust is a function of

A

operating rpm and tail rotor AOA

28
Q

Two primary directional control mechanisms of TR

A

AOA and weather vaning tendency of fuselage

29
Q

LTE and winds from the right

A
  • winds from right decrease AOA of TR, reducing effectiveness and requiring additional left pedal to maintain heading
  • additional left pedal depletes main rotor power and reduces directional control authority
  • so, in high power, right crosswind situations, may lose TR effectiveness
30
Q

LTE and winds from the left

A
  • winds from left increase AOA of TR –> increase TR AOA –> increase in TR effectiveness
  • if left wind excessive, disturbed airflow around TR may develop, resulting in loss of effectiveness
31
Q

Weather Vaning

A

winds in 120 to 240 region

nose will weathervane into wind

32
Q

TR VRS

A
  • 210 to 330
  • can cause TR to operate within its own recirculated airflow
  • causes TR thrust variations that can initiate yaw rates
  • if right yaw builds from this, may get into weather vaning and see yaw rate accelerate
33
Q

Main Rotor Disc Vortex Interaction

A
  • 280 to 330, less frequently 30 to 80
    can cause main rotor vortex to be directed onto TR, resulting in changes of AOA to TR
  • TR thrust can vary unpredictably
34
Q

Loss of TL

A
  • results in increased power demand and additional anti-torque requirements
  • if occurs in right turn, right turn will be accelerated; if near max power available –> Nr decay
  • can be caused by insufficient attention to wind direction and velocity
35
Q

Right sideward flight and LTE

A

same effect as right crosswind

36
Q

Factors increasing likelihood of LTE

A

high gross weight, high DA, arresting high descent rate

37
Q

Recovering from LTE

A
  1. Lower collective to reduce tq/arrest right yaw (if too high of descent rate, arresting descent may reinitiate LTE)
  2. Forward cyclic to increase airspeed, and if necessary, turning in direction of rotation (causes reduction in TR thrust req and produces streamlining effect)
  3. At low speeds/hover, full left pedal may stop right yaw (may take a few seconds/rotations to work). Neutralizing pedals or adding right pedal will only accelerate yaw rate
38
Q

Spring tension feature

A

with loss of both cables, provides positive pitch on TR equivalent to the antitorque requirements (left pedal) for a midposition collective setting

HAC (47 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions